Chain-tightener.



Patented Oct. 30, I900.

H. GREEN. CHAIN TIGHTENER.

(Application filed Nov. 27, 1899;:

(No Model.)

4 TRJR Nfioo m V A mam ur hl g I ll WHNEBEEE- n NORRB PETERS co, PHOYO-LITHQ. WASHINGTON, a. 42V

UNTTED STATES PATENT @EFicE.

HENRY GREEN, OF PEKIN, ILLINOIS, ASSIGNOR TO THE ACME HARVESTING COMPANY, OF SAME PLACE.

CHAlN-TlG HTEN ER.

SPECIFICATION forming part of Letters Patent No. 660,570, dated October 30, 1900.

Application filed November 27,1899. Serial No. 738,276. (No model.)

- cllain-tighteners.

The object thereof is to furnish an adjust.- able tightener for sprocket-chains and belts employed on various machines. The adj ustments permit of employing a rigid and a flexible tightener in one device, all of which will be hereinafter fully described.

In the appended drawings, Figure l is an elevation of a portion of the tightener secured to a part of the machine-frame, showing the sprocket-wheel and chain above it. Fig. 1 is a view of a plate shown in Fig. 1. Fig; 2

is a top viewof the same minus thesaid wheel and chain. Fig. 3 is an elevation of an adjustable arm used on the portion just described. Fig. & is a top view of Fig. 3. Fig. 5 is an edge view of a serrated cap. Fig. 6 is a top view of the same. Fig. 7 is a longitudinal section of portions of Figs. 2 and econobiued, showing a spring for use therewith. Fig. 8 is an elevation of the completed tightener on a larger scale.

In the figures, Aindicates a portion of the machine employing the tightener, and B is a metalplate suitably attached thereto. While this plate is not absolutely necessary in constructing and using my improved tightener, I show it and prefer to use it. To this plate is pivotally attached an arm D by means of a bolt 0, or in the absence of the plate B said arm may be directly attached to A. At the free end of the arm D is a slot E, concentric with the said bolt 0. Vertical adjustments may be given'thesaid arm D, and, when adjusted to the position desired, it is fixed at that point by means of a bolt F passing through said slot and a suitable aperture a in the plate B. It is understood, however, that a suitable depending lug on the portion A will answer, in the absence of the plate B, through which to pass the said bolt. At right angles to the plane of the arm described is a taperand its spring, as shownin Fig. 7.

ing post G, provided with abolt-hole H, running longitudinally through it, the purpose of which will be presently understood. Surrounding said post isan opening helical spring 'I, one end of which is inserted in an aperture J, Fig. 1, near the base of the said post G. An adjustable arni K, Fig. 3, has a tapering 6o hollow hub L, adapted to slip over the post The said hub is provided with teeth or serrations M on its outer end, and a cap N, Figs. 5 and 6, is likewise toothed on one of its faces and is adapted thereby to engage with the teeth M. The opposite face of the cap is made with a square projection to receive a wrench for purposes of adjustment. The outer free end of the spring I enters an aperture 0 in the said cap. A bolt P is passed through the postand cap and serves to keep the latter in engagement with said teeth M by a nut P. It is to be observed that tension, whether little or much, may beim parted to the spring and from that to the arm K in a direction to raise the latter against the chain; but this will be more thoroughly brought out as the description of the invention is proceeded with. On the end of the arm K opposite to the hub L is a fric- 8o tion-roller,Q, carried on a pin R, and on which the sprocket-chain runs.

The users of machinery emp'loying chaintighteners are often of dilierent opinions as to the best and most reliable form of this class of attachments. While one prefers a flexible tightener, another desires a stationary one, and still another a form that can be changed from a flexible to a stationary tightener at will, I have devised, therefore, onewhich 9o combines the requisites of each. In setting the machine up for use the arm D is attached to the portion A, substantially as described, the spring I is passed over the post or wrist G in the position shown and described, the 5 hub of the arm K is passed over said spring and post, and the cap N is set upon said hub.

The bolt .P is then inserted, after'which the desired tension is given the spring by applying a wrench to the cap and turning it against I00 the opening action of the spring until the desired stress is imparted to the arm. Then by tightening the said bolt the device is set for action. By this means roller Q is-brought up with considerable pressure against the chain to sustain it. The upward movement of the arm K is limited by alug S on the frame, means for adjusting same vertically slotted extremity of the arm D. When it is desired to make the device perfectly rigid as against the pressure of the chain upon a roller Q of the arm'K, the spring, by means of the. cap N, is tightened nearly to its highest limit. By this means the arm K is normally held against the said lug S. However, should an obstruction inadvertently get between the chain and either of sprockets or between the chain and roller Q the strain caused thereby causes the arm to give against the spring, and no damage is done. When the operator de' sires to have a flexible tightcuerlinstead of an almost rigid one, it is only necessary to partially lax the spring, and if more motion is required-the bolt F is loosened and thearm D pushed upward, as shown by dotted lines in Fig. 8. This forces the lug S away from engagement with the arm, and it will be seen that a nicety of adjustment may be had.

Thus far I have described two methods of adjustment of my tightener; but still another is possible by depressing arm K and passing a pin orbolt through it and a lug U, formed with-the arm I), as shown. Should an operator wish a perfectly-1 igid chain-tightener, this form will meethis desires. When so adjusted, it is only necessary to raise the said arm D by its slot and bolt F to the needed height to bring the roller Q and chain into contact. I do notlimit myself to any particular construction nor to the exactarrangementshown and described, as it may be varied in a number of ways and accomplish the desired ends. This device is equally\vell adapted as a belttightener and may be used for that purpose. Having thus described my invention, what I claim as new, and desire to secure by Letters arm adapted to receive the pressure, or strain.

of the chain or belt of the machine for the purposes set forth.

r 3. In a chain-tightener of the character described, an arm rigidly attached to the machine-frame, when in actual use, but capable of vertical adjustment thereon, a spring-0on trolled vibrating arm pivoted to such rigid arm and adapted to withstand pressure of the driving-chain to give under undue or unexpected strains, and a rigid stop for limiting the movement of said arm in the direction in which it is forced by the tension of the spring, substantially as set forth.

4. In a chain-tightener of the character described, an arm D pivoted to the machineing the desired pressure of the arm against the-chain substantially as and for the purposes set forth.

5. In a chain-tightener, an arm, at one end, pivoted to the machine-frame, the other end adapt ed for vertical adjustment on said pivot, substantially as described, a vibrating, or rocking arm pivoted on said adjustable arm and an adjustable spring for controlling the rocking arm as against the pressure of the chain substantially as set forth.

6. In a chain-tightener of the character described, an arm D pivoted on the machineframe atone end, there beingaslot in its opposite end, means passing through said slot and the machine for. permitting-adjustmentofsaid arm, a post, or wrist on the arm standing at right angles to the plane thereof, a spring surrounding the latter and'secured at one end against movement, an arm havinga hollow hub adapted to inclose the spring and post, a cap seated on said hub and-adapted to receive the opposite end of the spring, and

means for imparting tension to, the spring through the cap and holding the same after adjustment whereby tension is given the said arm controlled thereby, substantially as set forth and means for locking the two arms rigidly together.

7. In a chain-tightener of the character described, an arm D pivoted at one end to the machine, there beinga slot E in the opposite end thereof concentric with the pivot of said arm, a bolt I passing through said slot and secured to the machine-frame foradjusting the arm, a post, or wrist G at right angles to'the face of the latter and a spring I surrounding the post and entered in an aperture J, an arm K having the hollow hub L; the latter surrounding said spring and post and permitted to swing thereon, there being teeth, or serrations on the outer end of the hub, a cap N having similar serrations on its face adapted to engage with those of the hub, and an aperture 0 in said cap for receiving the free end of the spring, a bolt P with its tighteningnut passing through the post, hub and In testimony whereof I affix my signature in presence of two witnesses.

HENRY GREEN.

Witnesses:

W. H. BINNIAN, JAMES H. FITZMAURIOE. 

